KRAS and head and neck squamous cell carcinoma: Finally, tobacco-related malignancies, mainly represented by lung cancer and SCCHN, result from the activation of oncogenic pathways such as EGFR, K-RAS and H-RAS, PI3K-CA etc. The AKT serine-threonine kinases are common downstream effectors of these oncogenic pathways and are critical for tumorigenesis [29, 30].